I have a Yaesu Ft-100 with the ATAS-100, which has served me well for many years. However, recently the ATAS-100 has not been moving as it should. I've discovered that when driving down the road, it won't tune up or down anymore like it used to.

While standing still, if I tune it, and press lightly against the shaft, it will stop moving. I have built a manual box for tuning the antenna (for use with my KX3) that I can use for testing.

I did take the antenna apart (quite a number of times so far) and found that the threaded screw for moving the coil was not straight, so I bent it slightly and got it aligned better, but still won't turn when there is pressure (like from the wind as driving down the road). Didn't help.

I've tried to lubricate the antenna screw (silcon and WD-40) but still didn't help. The bottom white plastic insert at the coil moves up and down just fine, but apparently not with side pressure. Would it help to sand down the white plastic down to get some extra play around it? Could the clutch mechanism be messed up? Could the motor have lost some torque? (seems OK...) Could the screws that hold the shaft to the base be allowing some extra play that allows it to flex?

You can faff around forever trying to get it to work but it may be time to accept it has come to the end of its life. The bent screwed thread bar isn't a good sign and you'll never get it straight again so putting another motor on will just burn that one out quicker.

Thanks for the reply. When I measured the current, they were close to what you had. I took some sandpaper and took about .010" of an inch off the diameter of the internal slider. But when I pushed on it, is still stalls. I finally "pulled" on it and found that it didn't stall. So I just turned the base connector on my antenna mount 180 deg and it seems to be working OK. I'm not ready to give up on it yet.

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